/*
 * Copyright 2021 spring-boot-extension the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.livk.core.useragent.reactive;

import com.livk.core.useragent.UserAgentHelper;
import lombok.RequiredArgsConstructor;
import org.springframework.http.HttpHeaders;
import org.springframework.lang.NonNull;
import org.springframework.web.server.ServerWebExchange;
import org.springframework.web.server.WebFilter;
import org.springframework.web.server.WebFilterChain;
import reactor.core.publisher.Mono;

/**
 * <p>
 * AbstractReactiveUserAgentFilter
 * </p>
 *
 * @author livk
 */
@RequiredArgsConstructor
public class ReactiveUserAgentFilter implements WebFilter {

	private final UserAgentHelper helper;

	@NonNull
	@Override
	public final Mono<Void> filter(ServerWebExchange exchange, WebFilterChain chain) {
		exchange.getResponse()
			.beforeCommit(() -> Mono.deferContextual(Mono::just)
				.contextWrite(ReactiveUserAgentContextHolder.clearContext())
				.then());
		HttpHeaders headers = exchange.getRequest().getHeaders();
		return chain.filter(exchange).contextWrite(ReactiveUserAgentContextHolder.withContext(helper.convert(headers)));
	}

}
